A peroxide is easily decomposed by a heavy metal, heat, light or the like, and is known to be accompanied with generation of free radicals such as hydroxyl radical, hydroperoxy radical, an alkylperoxy radical, and an alkoxy radical.
It is thought that, in a living body, at a normal temperature, these free radicals are generated from a peroxide, which are involved in many diseases such as aging, cancer, and arterial sclerosis. In addition, it is reported that, in polymer electrolyte-type fuel cells and water electrolysis apparatuses, a free radical generated from hydrogen peroxide at a high temperature becomes a causative substance for deteriorating an electrolyte, in Dennis E, Curtin, Robert D. Lousenberg, Timothy J. Henry, Paul C. Tangeman, and Monica E. Tisack), J, Power Sources 2004, 131, 41 etc., and the free radical is one of factors of reducing performance in these apparatuses.
In recent years, for the purpose of preventing deterioration of an electrolyte with hydrogen peroxide, several studies concerning a hydrogen peroxide decomposition catalyst have been done. As the catalyst, a noble metal catalyst such as platinum and ruthenium has been reported, but a base metal catalyst is desired from a viewpoint of the cost and a resource amount. As an example of the previous disclosed base metal catalysts, there are exemplified a metal salt, a metal oxide and a metal complex, examples of the metal salt include rare earth phosphates, titanium phosphates, iron phosphates, aluminum phosphates, bismuth phosphates (Japanese Patent Application Laid-Open (JP-A) No. 2005-071760), and tungstates (JP-A No. 2005-019232), and examples of the metal oxide include tungsten oxide (JP-A No. 2005-019232), manganese dioxide (JP-A No. 2001-118591, JP-A No. 2003-123777, and JP-A No. 2005-135651), cobalt oxide (JP-A No. 2003-123777), ceriumoxide (JP-A No. 2004-327074), and iron ferrite (JP-A No. 2005-063902) In addition, as the metal complex, there are reported phthalocyanine iron complexes (JP-A No. 2005-135651, JP-A No. 6-154619) phthalocyanine cobalt complexes or phthalocyanine copper complexes (JP-A No. 6-154619), μ-oxo dinuclear iron complexes (JP-A No. 2004-296425), bipyridyl copper complexes (Helmut Sigel, Kurt Wyss, Beda E. Fischer, and Bernhard, Inorg. Chem. 1979, 18, 1354), and glycine or ethylenediamine/cobalt complexes supported in a polymer (D. T. Gokak, B. V. Kamath, and R. L. Ram, J. Appl. Polym. Sci 1988, 35, 1523).